Eaton 9387-FB-xx-R Open-frame, redundant fieldbus barrier

• For Foundation™ fieldbus networks in hazardous areas

• Pre-assembled system components for up to 5 intrinsically

safe spur connections

• For assembly into user-specified field enclosure

• Spurs compatible with FISCO and “Entity-certified”

fieldbus instruments

• Ergonomic mechanical design

• Pluggable system components without “gas free” constraints

• Optional, integrated surge protection for trunk and spurs

The 9387-FB-R (5-spur) Open-frame redundant fieldbus barrier

provides intrinsically safe spur connections from a high-energy trunk, for

connection to suitably certified Foundation™ fieldbus H1 instruments.

The unit comprises pre-wired and assembled system components on

a stainless steel baseplate, for installation into a suitably certified field

enclosure. Connection facilities are provided for the trunk and spur

wiring, as well as all electronic modules needed to support a fully

working Fieldbus Barrier. In a typical application, an Ex e (increased

safety) certified field enclosure will be selected to allow installation

in a Zone 1 hazardous area; third-party approval of the enclosure and

contents is normally required.

The assembly uses duplicated fieldbus barrier modules in

a redundant configuration to achieve significantly higher system

availability than equivalent ‘simplex’ units. The 9387-FB-R may

therefore be selected for critical process applications where failure

of the Fieldbus Barrier would otherwise result in unacceptable

downtime or lost production. It is also ideal for use in Fieldbus Safety

Instrumented Function (SIF) networks in which nuisance trips cannot

be tolerated. Failure annunciation to the host control system is

provided by means of an integrated Foundation™ fieldbus device with

Digital Input Function Block capability.

In common with conventional fieldbus barriers, each intrinsically

safe spur is capable of supporting a FISCO or ‘Entity’ certified fieldbus

device located in a Zone 0 or 1 hazardous area. The short-circuit

protected spurs are galvanically isolated from the trunk and require no

protective ground connection in the field.

The 9387-FB-R redundant fieldbus barrier assembly is based on

the 9370-FB range of products, which are supplied as complete,

factory-assembled systems that do not require additional wiring or

complex ancillary components. The electrical and mechanical aspects

of this design have been integrated to provide the industry’s first

complete, ergonomic solution for ‘High Energy Trunk’ applications in

hazardous areas.

Uniquely, the key modular components of the system (Fieldbus

Barrier, Terminator and Surge Protectors) may be ‘hot-plugged’ by

design and without gas-clearance procedures or separate isolating

switches. This virtually eliminates the risk associated with hazardous

area maintenance activities, speeds module replacement and avoids

the need for specialist operator training. Further optional features

include pluggable surge protection components for the fieldbus trunk

and individual spurs.

The 9387-FB-R Fieldbus barrier assembly is bus powered and

requires no additional power supply in the field. When used with a

fieldbus host control system, power for the trunk may be provided by

redundant MTL power supplies.